1. In the experiment, you will be measuring the time it takes for the solution t
ID: 480885 • Letter: 1
Question
1. In the experiment, you will be measuring the time it takes for the solution to turn blue. If you have initial concentrations of I- = 0.028 M, BrO3- = 0.016 M, H+ = 1.8 x 10-5 M, and S2O32- = 0.001 M, what is the concentration of S2O32- when the solution turns blue?
2. In the experiment, you will be measuring the time it takes for the solution to turn blue. If you have initial concentrations of I- = 0.018 M, BrO3- = 0.024 M, H+ = 1.8 x 10-5 M, and S2O32- = 0.006 M, what is the concentration of I- when the solution turns blue?
Explanation / Answer
6I-+BrO3-+6H+ --------->3I2+Br2-+H20
3I2+6S2O3--------->6I-+ 3S4O6-
I2+STARCH----------->BLUE COMPLEX
I2 formed in the first step of the reaction will first react with S2O3^2-. When all the S2O3^2- has reacted with I2, the solution will turn blue. Final concentration of S2O3^2- is zero.
------------------------------------------------
According to stoichiometry of the reaction 1 mol S2O3^2- reacts with 1mol I-. Molarity of I- that has reacted with 0.006M S2O3^2- is 0.006M.
Remaining in the solution = 0.018-0.006 = 0.012 M
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.